Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
  • F02M55/004—Joints; Sealings
  • F02M55/005—Joints; Sealings for high pressure conduits, e.g. connected to pump outlet or to injector inlet
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
  • F16L19/00—Joints in which sealing surfaces are pressed together by means of a member, e.g. a swivel nut, screwed on, or into, one of the joint parts
  • F16L19/02—Pipe ends provided with collars or flanges, integral with the pipe or not, pressed together by a screwed member
  • F16L19/0212—Pipe ends provided with collars or flanges, integral with the pipe or not, pressed together by a screwed member using specially adapted sealing means
  • F16L19/0225—Pipe ends provided with collars or flanges, integral with the pipe or not, pressed together by a screwed member using specially adapted sealing means without sealing rings
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S29/00—Metal working
  • Y10S29/043—Upsetting and flanging tube end
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49826—Assembling or joining
  • Y10T29/49908—Joining by deforming
  • Y10T29/49915—Overedge assembling of seated part
  • Y10T29/4992—Overedge assembling of seated part by flaring inserted cup or tube end
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49826—Assembling or joining
  • Y10T29/49945—Assembling or joining by driven force fit

Definitions

• the invention relates to an injection line connection for internal combustion engines according to the preamble of claim 1 and to a manufacturing method for a connection nipple of a pressure connection thereof.
• Injection lines with a sufficient wall thickness are required for upsetting the ball nipple, since otherwise too little material is available for the upsetting.
• outer diameters D of 6 mm and wall thicknesses s of 2 mm are common, so that sufficient material is available for the upsetting of suitable ball nipples.
• lower injection pressures are sufficient for numerous other types of internal combustion engines, for example for engines with petrol injection and so-called * pre-chamber diesel engines for passenger cars, and thus injection lines with smaller wall thicknesses would also suffice, if then enough material would still be available for a molded-on connecting nipple.
• the invention is based on the object of perfecting the injection line connection together with its pressure connections in such a way that, if possible, all of the above-mentioned defects are avoided and reliable fixing and sealing of the injection lines via a on the inner cone every arrival end fitting supported connection nipple despite avoiding internal pinch folds and without the risk of constriction of the injection line at the fixing point and also without the risk of later contamination of the fuel delivered by dirt or material particles detached from the injection line.
• GB - A - 1756/1912 discloses, in relation to its clear width, very thin pressure lines in connection with spherical outer surfaces of support lugs on pressure rings, having only a small cone angle in the range from 30 to 45 °. The consequence are relatively long and thin cross-sectional support lugs that cannot withstand major constriction forces when tightening a nut. These pressure connections are primarily intended for pipes in connection with steam boilers, where the
• a certain elasticity of the pressure rings is desired here, so that in the event of a temperature expansion of the pressure pipe, a certain axial displacement of the connecting nipple in the inner cone of the connecting piece is possible, the inner cone of which for this purpose, for example, only has a cone angle of 30 °.
• the disclosed pressure lines with a ratio of their outside diameter to their wall thickness of approximately 10: 1 can also be easily flanged to the outside by a support attachment of a pressure ring, the pressure connections disclosed in the patent are nevertheless to injection lines of injection systems of usual injection pressures up to over 500 bar completely unsuitable and would never lead to a usable tight pressure connection. It is therefore understandable that this state of the art, despite the problem of creating suitable, highly stressed pressure connections for injection lines which has existed for over 50 years, has not given any excitation to the present invention.
• the strong dimensioning of the pressure rings and support lugs in relation to the area acted upon by the injection pressure and proportional to the outside diameter of the injection line and, on the other hand, the relatively very short dimensioning of the latter ensures that in the injection line connection according to the invention, despite the connection cone of each connecting nipple and so that no constriction force can be caused at the connecting nipples at each support attachment. Due to the flanging of the line material around the support lug, there is at the same time such a large wedge-like support surface of the support ring on the injection line with such a large mean diameter that when the union nut is tightened there is no longer any fear of the pressure ring rotating with the union nut . It is also advantageous that everyone
• connection nipple of the injection line are formed by the inner surface thereof, which according to the above is particularly smooth and reduces the risk of contamination of the fuel compared to connection nipples customary today.
• the proposed connection nipples can also be subsequently cleaned better than the connection nipples common today because the pinch folds roughening the inner surfaces are avoided.
• the invention also includes an advantageous method for producing the connecting nipples of an injection line of the invention .
• Injection line connection which is characterized in claim 10.
• FIG. 1 shows an embodiment of the injection line connection at the location of a pressure connection in an enlarged axial section
• FIG. 2 shows the pressing tools of a pressing device that receives the end of a fuel injection line according to FIG. 1 for its flare after performing a first operation for flaring the end of the line (in a side view that is less enlarged than FIG. 1, partly in the axial direction) ⁇ cut);
• FIG. 3 shows the pressing device in an identical illustration, but with a pressure ring used as a die after a second work cycle has been carried out;
• the injection line connection shown in FIG. 1 of an otherwise conventional and therefore not shown embodiment for connecting a pressure connection of a fuel injection pump of a prechamber diesel engine to an associated injection nozzle located on its working cylinders has an injection line 1 with an outer diameter D. of 4.0 mm, a wall thickness s of 1.0 mm and thus a clear width d of 2 mm, which at both ends via a pressure connection each shown in FIG. 1 with a connecting piece 2 on the one hand to the injection pump and on the other is connected to the injection nozzle. Since neither the injection pump nor the injection nozzle is the subject of the present invention and both can correspond to any generally customary design, there is no need to describe and describe them in more detail here.
• connection-side end of the injection line 1 forms a connection nipple 3, which is explained in more detail below and which - from a union nut 4 via a pressure ring 6 supported on one side on an inner flat annular shoulder 5 thereof and on the other hand on a rear support surface of the connection nipple 3
• the Pressure ring 6 covers the connecting piece 2 radially beyond its conical opening.
• the pressure ring 6 consists of a profiled strip which has been cut to length and rolled into the 15 ring to form a separation point 6 'and is firmly connected to the connecting nipple 3 by a press fit and its outer diameter d is approximately twice the outer diameter D of the injection line 1. It is provided with a nipple-side ring-shaped support projection 20 10, the nipple-side edge of which is rounded in the ring cross-section with a radius r of approximately 0.5 mm.
• the support lug 10 has from its root a conically tapered outer circumferential surface 11, the cone angle ⁇ of which lies in the region of the cone angle ⁇ of the inner cone 7 of the connecting piece 2.
• the connecting nipple 3 consists of the free end of the injection line 1, which is flanged around the support projection 10 and on the outside at the same time forms the sealing cone 9.
• Each support projection 10, 30 has measured from the root end of the area of the injection line surrounding it 1 from an axial length L lying in the region of the wall thickness s of the injection line 1 and a wall thickness w 'of approximately 1/4 of the outside diameter D of the injection line 1.
• the bore 12 of the pressure ring 6 is provided at its the supporting ⁇ ? "Approach 10 opposite end a trumpet-shaped Er ⁇ furtherance 13. 1
• the outward approach to the Stütz ⁇ 10 herumgebördelte end portion of the injection line a s smaller wall thickness compared to the wall thickness of w on.
• the outer diameter d 3, which causes a large wall thickness, of the pressure ring 6, which in the recess of the union nut 4 could be approximately up to three times the outer diameter D of the injection line 1, and the likewise large root-side wall thickness w 'of the support projection 10, which at the root end of their vcm the flanged end of the outer circumferential surface 11, which is flanged, is approximately 1/4 of the outer diameter D of the injection line 1 and could also be larger, in association with the relatively short axial length L lying in the region of the wall thickness s of the injection line 1 of the support lug 10 is essential because the high operating pressure occurring in the injection line (up to over 500 bar) and the operating vibrations of internal combustion engines at the pressure connections concerned here require considerable axial tightening forces in order to ensure reliable tightness during operation.
• FIG. 2 to 4 illustrate a preferred method of manufacture of the connecting nipple 3 according to FIG. 1 by means of a pressing device in three work steps, after which a die used in the second and third work step for flanging the end of the injection line 1 in the third work step is firmly pressed together with the end of the injection line 1 crimped around its support shoulder 10 so that it now acts as a lost tool the injection line 1 remains and there forms the pressure ring 6 which remains firmly connected to the connecting nipple 3.
• the pressing tool has different die parts 15, 15a and 15b, each consisting of two half-shells, and also different pressing dies 16, 16a and 16b. While the die part 15 only requires a bore 17 which simultaneously receives the injection line 1 for the first operation, the die 16 required for the first operation is not only provided with a mandrel 18 rounded at its base in accordance with the flanging of the injection line 1 , which after the pressing process still penetrates relatively deeply into the injection line 1, but also with a recess 19 which allows the crimped line end to be received.
• the die part 15a used to carry out the second operation accommodates, in a stamp-side extension of its bore 17 'which accommodates the injection line 1 with play, a pressure ring 6 which serves as a die and which, according to FIG. 3, was lined up on the injection line 1 before the start of flanging and is now pushed towards the flared line end and protrudes with its support projection 10 from the die part 15a in the visible manner on the stamp side.
• the press ram 16a here has a recess 19 'around the mandrel 18 which is deeper than the recess 19 of the press ram 16 by the axial length of the support projection 10, so that at the end of the pressing process provided here and thus when the end face of the press ram is seated 16a on the counter surface of the matrix part 15a, the crimped end of the injection line 1 is just firmly pressed against the free end of the support projection 10.
• the play between the bore 17 'and the injection line 1 serves to prevent the latter from being Process to give the possibility of a corresponding axial displacement ** " -
• the die part 15b for carrying out the third working cycle again receives the injection line 1 together with the pressure ring 6 without play, so that no material of the injection line 1 can escape to the outside behind the pressure ring 6 during this strongest pressing operation.
• the press ram 16b here has on its end face around a somewhat modified mandrel 18 * around an insert 20 corresponding to the inner cone 7 of a connecting piece 2, so that the flanged part of the injection line 1 at the end of this operation on its outer surface at the same time forms a sealing cone 9 aligned with the inner cone 7.
• the ratio D: s of the injection line is approximately 4: 1, although this ratio could also be in the range from 3: 1 to 5: 1, depending on the respective requirements.
• the cone angle ⁇ of the inner cone 7 of the connecting piece 2 shown in the exemplary embodiment at 60 ° corresponds to a value which has been tried and tested in practice, but could also deviate from this value by an amount of up to + 10 °.
• the outer diameter d EL of the pressure ring could also be in the range between approximately 1.8 times and approximately three times the outer diameter D of the injection line 1.
• the radius r of the nipple-side edge of the support projection 10 could be in a range of approximately 0.2 to 0.4 times the wall thickness s of the injection line 1, as is shown in FIG It is also possible within the scope of the invention to produce the pressure ring 6 in a chip-free or non-cutting manner as a seamlessly closed ring, instead of from an elongated profile strip that is rolled into the ring by means of a device to form the separation point, either as a rotating ring turn part from the solid or cold-pressed as a cold pressed part from Drafft.
• the wall thickness s of the injection line 1 smaller wall thickness w of the herumgebördelten around the support projection 10 end part of the line in the described flanging also can already result by itself, so the invention is not yet at the darge presented wall thickness reductions of said end portion bonded .
• the invention also includes injection lines with diameters larger than 4.0 mm, insofar as they are suitable for fuel injection in internal combustion engines.
• the invention is also not tied to a press fit connection of the pressure ring 6 with the injection line 1. If such a connection is also preferred in order to reliably prevent the pressure ring 6 from turning when the union nut 4 is tightened - and thus wear and tear on the injection line 1 - the conical circumferential surface 11 of the support projection 10 already results in such a large outer support surface of the pressure ring 6 on the connecting nipple 3, that as a rule there is no need to fear that the pressure ring 6 will not rotate with the union nut 4 even without a press fit.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Fuel-Injection Apparatus (AREA)

Priority Applications (4)

Applications Claiming Priority (1)

Publications (1)

Family

ID=6198589

Family Applications (1)

Country Status (8)

Families Citing this family (32)

Citations (3)

Family Cites Families (20)

• 1983
  • 1983-05-09 DE DE3316979A patent/DE3316979C2/de not_active Expired
• 1984
  • 1984-04-18 US US06/694,399 patent/US4705306A/en not_active Expired - Fee Related
  • 1984-04-18 DE DE8484901741T patent/DE3465364D1/de not_active Expired
  • 1984-04-18 JP JP59501721A patent/JPS60501818A/ja active Granted
  • 1984-04-18 EP EP84901741A patent/EP0142525B1/de not_active Expired
  • 1984-04-18 WO PCT/DE1984/000092 patent/WO1984004566A1/de active IP Right Grant
  • 1984-05-08 IT IT12508/84A patent/IT1180757B/it active
  • 1984-12-04 DK DK577284A patent/DK150666C/da not_active IP Right Cessation
  • 1984-12-04 FI FI844771A patent/FI77723C/fi not_active IP Right Cessation

Patent Citations (3)

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